Text Data

Area Forecast Discussion

989
FXUS64 KSHV 220601
AFDSHV
Area Forecast Discussion
National Weather Service Shreveport LA
1201 AM CST Thu Feb 22 2018
.AVIATION...
For the 22/06z TAFs, convection continues along a quasi-
stationary front from the South Texas Coast northeast to the
Toledo Bend Country, and into North Louisiana and South Arkansas.
Latest water vapor loops indicate indicate some mid-level dry air
moving across Central Texas, and this has resulted in a gradual
diminishing of the precip west of a line from KDEQ to KJSO.
However, the leading edge of a secondary plume of moisture is
nearing the Rio Grande and will move over our area during the TAF
period. This will likely result in redevelopment of convection
farther west across Southeast Oklahoma, Southwest Arkansas, and
East Texas by mid to late Thursday morning.
Flight conditions continue to vary widely, but most TAF sites will
generally remain MVFR or lower for much of the period. Showers and
thunderstorms should taper off across Southern Arkansas and
Northern Louisiana by 22/15z, but the precip is expected to
become re-focused farther to the west around the same time, and
will persist through the remainder of the period prevailing at all
sites except KELD and KMLU.
CN
&&
.PREV DISCUSSION... /issued 837 PM CST Wed Feb 21 2018/
UPDATE...
Have made no changes to the current Flash Flood Watch which
remains in effect through 6 am Thursday Morning. Cold front which
has pulled up stationary late this evening was oriented from just
north of BPT to just north of ESF attm. Best upper level forcing
and overrunning frontal ascent will take place across our
southeast zones for the remainder of the night so for this reason,
have increased pops to high end categorical variety. Good
agreement from the HRRR and the latest 00z NAM output for a
decreasing trend in precip coverage and intensity across our
northwest zones. Pops were scaled back to low end chance variety
across our northwest after midnight so have left that pop grid
unchanged.
Temperatures remain tricky overnight as hourly temperatures have
wavered back and forth in the colder airmass across NE TX and
portions of NW LA and SW AR over the past hour. The stationary
front to our south will not begin returning back northward until
the daytime hours on Thu so plan on keeping temperatures nearly
stationary for the remainder of the night and the currently fcst
hourly grid output reflects this trend well.
No other changes are necessary attm...13.
PREV DISCUSSION... /issued 555 PM CST Wed Feb 21 2018/
AVIATION...
For the 22/00z TAFs, IFR/LIFR flight conditions are expected to
persist at most terminals for the entire TAF period. Widespread
convection will also continue without much of a break for the next
24 hours. The rain may be heavy at times. In fact, the initial
conditions are expected to change very little for the duration of
the period. The exceptions might be some portions of Southeast
Oklahoma, extreme Southwest Arkansas, and Northeast Texas,
including KTXK and KTYR. The convection may taper off a bit during
the early morning hours, but is still expected to prevail for much
of the daytime hours of Thursday.
CN
&&
.PRELIMINARY POINT TEMPS/POPS...
SHV 52 65 60 74 / 100 70 80 50
MLU 52 75 64 79 / 100 70 50 30
DEQ 43 53 50 63 / 100 80 90 90
TXK 45 55 54 66 / 100 70 90 90
ELD 45 63 60 73 / 100 70 70 60
TYR 44 56 52 69 / 90 70 90 70
GGG 46 60 55 72 / 100 70 80 70
LFK 55 70 60 79 / 100 60 60 40
&&
.SHV WATCHES/WARNINGS/ADVISORIES...
AR...Flash Flood Watch until 6 AM CST Thursday for ARZ050-051-059>061-
070>073.
LA...Flash Flood Watch until 6 AM CST Thursday for LAZ001>006-010>014-
017>022.
OK...Flash Flood Watch until 6 AM CST Thursday for OKZ077.
TX...Flash Flood Watch until 6 AM CST Thursday for TXZ096-097-108>112-
124>126-136>138-149>153-165>167.
&&
$$
09/13